• 해양환경안전학회지
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• 제27권7호
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• pp.1124-1128
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• 2021

선박으로부터 발생하는 배출가스에 대한 규제가 강화되고 이를 해결하기위한 대안으로 전기추진시스템의적용이 대형상선에서부터 중·소형선박에 이르기까지 그 사용이 증가되고있다. 전기추진시스템의 효율 향상을 위한 방법으로 발전원의 개선, 배터리·연료전지·태양광 등의 친환경 발전원의 시스템 연계 및 정류기, 전력변환장치, 추진전동기의 개발과 제어방식의 연구를 들 수 있다. 그 중 정류방식에 있어 상천이변압기과 다이오드를 이용하는 방식이 널리 사용되었으나, 직류배전을 이용한 친환경발전원의 계통 연계, 가변속 발전원의 사용, 중·소형 전기추진시스템의 적용을 통해 전력용 반도체 소자를 이용한 AFE정류기에 대한 수요가 증대되고 있다. 이러한 AFE 정류기를 제어하는 방식에 있어 기존의 비례적분제어기가 아닌 신경회로망을 이용한 방식을 본 연구에서는 제안하였다. 기존의 제어기 데이터를 활용하여 Matlab/Simulink를 통해 학습한 신경회로망제어기를 설계하고 PSIM을 통해 설계된 정류시스템에 신경회로망 제어기를 적용하여 부하변동에 따른 직류출력단의 파형과 역률 개선의 유효성을 확인하였다. 이는 공간이 협소한 중소형 친환경 선박의 정류시스템으로써 적용이 가능하다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2014년도 추계학술대회 논문집
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• pp.205-206
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• 2014

본 논문에서는 3-레벨 인버터 시스템에서 공통 모드 전압 변동 제거를 위한 새로운 Medium Vector PWM(MVPWM)을 제안한다. 제안된 MVPWM의 특징은 다음과 같다. 1) 스위칭 상태와 관계없이 공통모드 전압은 일정하게 유지된다. 2) 무게 중심좌표계 방법에 의하여 구현되므로 구현이 간단하고 직관적이다. 본 논문에서는 시뮬레이션을 통하여 제안된 MVPWM의 위와 같은 특성을 밝히고 태양광 인버터의 제어에 적합함을 입증하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2010년도 하계학술대회 논문집
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• pp.307-308
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• 2010

본 논문에서는 신재생에너지 발전 설비 증가에 따른 계통의 불안정성을 극복하기 위하여, 독일 BDEW(German Association of Energy and Water Industries)가 제정한 특고압(Medium Voltage) 계통 연계 신재생 에너지 발전 시스템에 대한 계통 연계 규정에 대해서 기술한다. 특히, 태양광 인버터 관점에서 독일의 새로운 계통연계 규정이 요구하고 있는 내용에 대해서 설명한다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2011년도 한국컴퓨터종합학술대회논문집 Vol.38 No.1(D)
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• pp.267-268
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• 2011

Recent research activities in cooperative communication focus on achieving energy efficiency and reliability. Relay selection strategy for cooperative communication improves the performance significantly. However, due to imbalance consumption of power, network might die earlier and more than 90% energy remains unused. In this paper, we provide a framework of an energy-efficient medium access control protocol that minimizes these problems and improves energy efficiency.

• 대한전자공학회논문지
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• 제2권2호
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• pp.2-8
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• 1965

This paper shows the characteristics of microwaves in a plasma medium bounded by a waveguide. A standing wave detector which has VSWR less than 1.05 is designed and constructed. The electromagnetic waves which propagate through the plasma is reflected partly by the interaction between the external magnetic fields and plasma. The plasma is consisted of the electrons and positive ions ionized by high temperature of tungsten filament inserted in the waveguide. The transmitted power through the plasma was reduced by the amount of 1.5db from the reference.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2013년도 전력전자학술대회 논문집
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• pp.441-442
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• 2013

This paper deals with 100kW IPMSM drive inverter for Midium Duty Electric Car. First, it introduces about hardware structure of inverter. Then performance of IPMSM drive system is confirmed through experiments.

• 통상정보연구
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• 제5권1호
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• pp.21-38
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• 2003

21 century, Korea enterprise which run business in global market, has rapidly change. So, achievement of international competitive power is very important. IT(Information Telecommunication) Technology is play a leading role in this field. In fact, Korea enormous invest in informational technology field and hold the first place in informational quotient(information super-highway, server computer, mobile networking and firm's web site etc). But, materialization of information management effect consider how to cope with the situation. Korea SMEs(Small and Medium Enterprises) is fundamental in Korea economy. So Korea SMEs must active the international competitive power by information management and advance to a higher position. In conclusion, SMEs of information management is require that SMEs' CEO and CIO are must self-help to in this field. And governments improvement of connected with the related system in these field.

• Journal of Electrical Engineering and Technology
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• 제12권2호
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• pp.632-642
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• 2017

This paper presents an improved approach towards reducing the switching loss of insulated gate bipolar transistors (IGBTs) for a medium-capacity-class power conditioning system (PCS). In order to improve the switching performance, the switching operation is analyzed, and based on this analysis, an improved switching method that reduces the switching time and switching loss is proposed. Compared to a conventional gate drive scheme, the switching loss, switching time, and delay are improved in the proposed gate driving method. The performance of the proposed gate driving method is verified through several experiments.

• 정보통신설비학회논문지
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• 제10권4호
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• pp.115-120
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• 2011

Recently flash memory is widely used in various mobile devices as storage medium. Nonvolatile memory can be divided into two categories: NAND- and NOR-type flash memory. NOR flash memory is mainly used to store instruction codes for operation; while NAND for data storage. However, NAND does show more economical benefits, that is, it is approximately 30~40% cheaper than NOR flash. Therefore it can be useful to improve NAND flash performance by replacing NOR flash with NAND flash combining with various buffer systems.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.606-610
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• 1991

A relay is the one of small electrical components for automobiles and used for industry widely. We have developed the automation system for relay assembly and test to make it improve the productivity and decrease the man power. In order to determine the objective process of automation, we investigated 6 small and medium sized-enterprises and 1 greate sized-enterprise producing relays. And, we selected 2 model enterprises of them. One of the two is the system to develop. The scope of our study is the analyse of the conventional workcell, the determination of the system specification, the design of the system layout, the determination of the system cycle time, the design of the system mechanism, and the development of the controller for the system. We think that the developed system may be solve the technical and the economical problems interrupted efficiential automation of domastic small and medium sized-enterprises, and improve the international competitive power.